The name Cowhage is Hindustani, and in the modern way is written Kiwânch, which is generally derived from the Sanskrit Kapi-Kachchu, monkey’s itch (Dr. Rice); the corruption into Cow-itch is absurd. Mucuna is the Brazilian name of another species mentioned in 1648 by Marcgraf.[755]

Description—The pods are 2 to 4 inches long, about ⁴/₁₀ of an inch wide, and contain 4 to 6 seeds; they are slightly compressed and of a dark blackish brown. Each valve is furnished with a prominent ridge running from the apex nearly to the base, and is densely covered with rigid, pointed, brown hairs, measuring about ⅒ of an inch in length. The hairs are perfectly straight and easily detached from the valves, out of the epidermis of which they rise. If incautiously touched, they enter the skin and occasion an intolerable itching.

Microscopic Structure—Under the microscope the hairs are seen to consist of a single, sharply pointed, conical cell, about ¹/₄₀ of an inch in diameter at the base, with uniform brownish walls 5 mkm. thick, which towards the apex are slightly barbed. Occasionally a hair shows one or two transverse walls. Most of the hairs contain only air; others show a little granular matter which acquires a greenish hue on addition of alcoholic solution of perchloride of iron. If moistened with chromic acid, no structural peculiarity is revealed that calls for remark. The walls however are somewhat separated into indistinct layers, the presence of which is confirmed by the refractive power displayed by the hairs in polarized light.

Chemical Composition—The hairs when treated with sulphuric acid and iodine assume a dark brown colour. Boiling solution of potash does not considerably swell or alter them. They are completely decolorized by concentrated nitric acid.

Uses—Cowhage is administered for the expulsion of intestinal worms, especially Ascaris lumbricoides and A. vermicularis, which it effects by reason of its mechanical structure. It is given mixed with syrup or honey in the form of an electuary.

The root and seeds are reputed medicinal by the natives of some part of India. The pods when young and tender may be cooked and eaten.

SEMEN PHYSOSTIGMATIS.

Faba Calabarica, Faba Physostigmatis; Calabar Bean, Ordeal Bean of Old Calabar, Eseré Nut, Chop-nut; F. Fève de Calabar; G. Calabarbohne.

Botanical OriginPhysostigma venenosum Balfour, a perennial plant resembling the common Scarlet Runner (Phaseolus multiflorus Lam.) of our gardens, but having a woody stem often an inch or two thick, climbing to a height of 50 feet or more. It grows near the mouths of the Niger and the Old Calabar River in the Gulf of Guinea.

The imported seeds germinate freely, but the plant, though it thrives vigorously in a hothouse, has not yet, we believe, flowered in Europe. It has already been introduced into India and Brazil. In the latter country Dr. Peckolt, late of Cantagallo, has raised plants which have blossomed abundantly, producing racemes of about 30 flowers each, pendent from the axils of the ternate leaves.